Called Blackphone, which was first announced earlier this year, the handset makes use of a customized version of Android called PrivatOS and comes kitted out with a full suite of privacy-enabled applications.

On the hardware side of things the Blackphone is reasonably impressive:

4.7-inch HD IPS screen

>2GHz quad core CPU

2 GB RAM

16 GB storage

LTE

HSPA+

Front camera >8Mpx with flash, plus rear camera

Some of these spec points are currently fluid and will be nailed down closer to release, which is currently slated for June 2014.

The Blackphone apps comes with a full year's subscription, after which the user will need to cough up $10 per month to continue using the suite or go back to using unencrypted comms.

The handset is unlocked and can be used on any compatible network – no carrier support is needed for the encryption and privacy tools.

Blackphone is backed by some big names, and is the brainchild of security and technology specialists including Phil Zimmermann, the creator of the PGP encryption tool.

The handset is certainly an interesting idea, but I'm skeptical that there are enough people out there willing to hand over $630 for the hardware plus then be committed to a $120 a year plan to make this work, even if we spread the net wide and include enterprise in this category. Silent Circle is targeting 10 million sales per year over the first three years, which sounds like a lot given hiow niche it is. Perhaps the biggest niche for this device is the void left by the implosion of of BlackBerry.

And while Blackphone is the first security and privacy focused smartphone, I don't expect it to be the only one for long, and I wouldn't be surprised to see bigger players – perhaps Samsung, which has quite a focus on BYOD – to enter the arena.

On top of that, this is a new handset running a new operating system, so the scope for teething troubles and bugs is high at this stage.

Oh, and remember, to make use of this, the person you are communicating with either needs a Blackphone, or needs to be using Silent Circle apps on their Android or iOS device.